I have one Euphorbia x Martini and one Euphorbia with reddish leaves, these plants are being affected by a white mould on the leaves, they look really awful. We did not prune the plants back after flowering, could this possibly be the cause, or is it a disease which can be treated?

I understand you give free advice on plant care, I would be very grateful if you could help with this problem.

We are also looking for small colorful evergreen plants for a patio container, have you any suggestions.

If the white mould is mainly on the top of the leaf surfaces it is probably powdery mildew which is caused by dry conditions at the root area.

If the white mould is mainly on the undersides of the leaves it is more likely to be downy mildew caused by conditions that are too damp in the root area.

Either way if the foliage looks really unsightly cut it all down to ground level, Euphorbia (being a close relative of bindweed) are quite hard to kill and should re-sprout from the base. When it re-sprouts try and correct the watering regime according to which type of mildew it is.

In reference to the second part of your question, we are trying to promote our new plant search facility on our website, See this:

I have ticked the relevant boxes for you, Evergreen, hardy (I presume you want hardy) and suitable for growing in containers. Please use the facility to search for plants in future and if you like it tell your gardening friends about it!